Atlas of Genetics and Cytogenetics in Oncology and Haematology

Taking over the Atlas
Dear Colleagues,
The Atlas, once more, is in great danger, and I will have to proceed to a collective economic lay-off
of all the team involved in the Atlas before the begining of April 2015 (a foundation having suddenly
withdrawn its commitment to support the Atlas).
I ask you herein if any Scientific Society (a Society of Cytogenetics, of Clinical Genetics, of Hematology,
or a Cancer Society, or any other...), any University and/or Hospital, any Charity, or any database would be
interested in taking over the Atlas, in whole or in part. If taking charge of the whole lot is too big, a
consortium of various actors could be the solution (I am myself trying to find partners).
Could you please spread the information, contact the relevant authorities, and find partners.
Survival of the Atlas will be critically dependant upon your ability to find solutions (and urgently!).
Kind regards.
Jean-Loup Huret jlhuret@AtlasGeneticsOncology.orgDonations are also welcome
If each casual visitor gives 3 Euros or Dollars, the Atlas is saved in a week !
If each professional gives 100 Euros or Dollars once a year (now), the Atlas is saved in 2 weeks !
Don't let the Atlas imminent demise
Note: we send fiscal receipts for donations equal or above 50 Euros or Dollars

The human TRA locus is located on the chromosome 14 on the long arm at band 14q11.2. The orientation of the locus has been determined by the analysis of translocations, involving the TRA and TRD loci, in leukemia and lymphoma.

The most 5' TRAV genes occupy the most centromeric position, whereas the TRAC genes, 3' of the locus, is the most telomeric gene in the TRA locus.

The organization of the TRAJ segments on a large area is quite unusual and has not been observed in the other immunoglobulin or T cell receptor loci.

Moreover the TRD locus is nestled in the TRA locus between the TRAV and TRAJ segments. V-J-rearrangements in the TRA locus therefore result in deletion of the TRD genes localized on the same chromosome. That deletion occurs in two steps, that is a deletion of the TRD genes, involving specific sequences located upstream from TRDC (sequence pseudo J alpha) would take place before the TRAV-J rearrangement.

Among the variable genes are included five genes designated as TRAV/DV which belong to five different subgroups and which have been found rearranged either to TRAJ or to TRDD segments and can therefore be used in the synthesis of alpha or delta chains.

The total number of human TRA genes per haploid genome is 116 of which 96 to 98 genes are functional. Enhancer sequences have been characterized 4.5kb 3' from TRAC.

Proteins encoded by the TRA locus are the T cell receptor alpha chains. They result from the recombination (or rearrangement), at the DNA level, of two genes: TRAV and TRAJ, with deletion of the intermediary DNA to create a rearranged TRAV-J gene. The rearranged TRAV-J gene is transcribed with the TRAC gene and translated into an T cell receptor alpha chain.

Translation of the variable germline genes involved in the TRAV-J rearrangements are available at IMGT Repertoire Protein displays. TRA V-J rearrangements can be analysed using the IMGT/V-QUEST tool.

Translocations which frequently result from errors of the recombinase enzyme complex (RAG1, RAG2, etc.), which is responsable of the Immunoglobulin and T cell receptor V-J and V-D-J rearrangements. TRAV or TRAJ recombination signals or isolated heptamer are observed at the breakpoints.